The invention disclosed relates to a method of manufacturing packs of cigarettes provided with a hermetically sealed wrapper.
Conventional cigarette packagings comprise an inner wrapper of paper, faced on one side with a sheet of tin foil (silver paper), and an outer wrapper which consists of paper, in the case of crush packs, or of a cardboard box in the case of flip-top rigid packs with a hinged lid. The outer wrapper is enveloped in its turn by a covering of transparent, substantially airtight material, the overlapping edges of which are bonded or heat-sealed together. Such a covering is sufficient, in most instances, to guarantee the cigarettes adequate protection against damp, and to afford a measure of insulation from the surrounding environment such as will maintain their organoleptic properties intact.
It has been discovered, however, that for cigarettes of especially aromatic flavor, or those destined for a long shelf life in hot or humid climates, the protection afforded by a covering and wrappers as described above will not suffice to ensure that the properties of the cigarettes remain unaffected in the long term.
Cigarette packaging machines currently available on the open market are incapable of producing packs with a faultlessly hermetic seal.
The object of the invention is to provide a method of manufacturing a wrapper such as will ensure a complete isolation of the packaged cigarettes from the surrounding environment.